Field of the Invention
The present invention relates to ferroelectric ceramics, a PZT film and a manufacturing method thereof, and a manufacturing method of ferroelectric ceramics.
Description of a Related Art
A conventional manufacturing method of Pb(Zr,Ti)O3 (hereinafter, referred to as “PZT”) perovskite-type ferroelectric ceramics will be explained.
A SiO2 film having a thickness of 300 nm is formed on a 4-inch Si wafer, and a TiOx film having a thickness of 5 nm is formed on the SiO2 film. Next, for example, a Pt film having a thickness of 150 nm oriented in (111) is formed on the TiOx film, and a PZT sol-gel solution is applied onto the Pt film by using a spin coater. Spin conditions at this time are such that the wafer is rotated at a rotation rate of 1500 rpm for 30 seconds and is rotated at a rotation rate of 4000 rpm for 10 seconds.
Next, the applied PZT sol-gel solution is heated and held on a hot plate at 250° C. for 30 seconds to be dried, and moisture is removed, and then it is further heated and held on a hot plate maintained at a high temperature of 500° C. for 60 seconds to thereby be subjected to temporary calcination. A PZT amorphous film having a thickness of 150 nm is generated by repeating this several times.
Subsequently, the PZT amorphous film is subjected to an annealing treatment at 700° C. by using a pressurizing-type lamp annealing device (RTA: rapidly thermal anneal) to carry out PZT crystallization. The PZT film thus crystallized is constituted of a perovskite structure (for example, refer to Patent Literature 1).
[Patent Literature 1] WO 2006/087777